1. Field of the Invention
The invention relates to a device and method for monitoring of rotating machine elements.
2. Description of Related Art
U.S. Patent Application Publication 2004/024499 describes how the coupling of a drive shaft of a VTOL aircraft is monitored using magnetostrictive sensors. Here, the sensors are attached to a rigid sleeve. On the end of each shaft, a magnetic target, for example, a permanent magnet, is mounted to the rotating flexible coupling. The target can also be formed of components of the coupling. This target is detected by way of sensors in the rigid sleeve. The rigid sleeve is advantageously arranged without any mechanical contact to one of the two coupling halves.
A similar principle is described in German Patent Application DE 195 06 471. In this document, the displacements of rotating shafts are monitored with inductive sensors, for example, eddy current sensors. This method is also suitable for monitoring of the displacements of couplings on comparatively slow-running shafts, for example, in mills. In order to measure one or more mill shafts in operation, inductive proximity sensors are used. These inductive proximity sensors are attached, for example, to stands on a separate base frame. This procedure is complex.
In contrast to U.S. Patent Application Publication 2004/024499, International Patent Application Publication WO 2009/011638 A1 proposes monitoring of a two-part coupling with a permanent magnet which is inserted into one half of the coupling and a two-dimensionally readable Hall sensor is located in the other half of the coupling. There is also a reference sensor for determining the rotary position.